Anyone hear the "wall of sound"?

It was before my time but the Grateful Dead experimented with a system 35 years ago comprised of nearly 650 loudspeakers powered by 89 300-watt Mcintosh MC2300 amplifiers and and three 350-watt McIntosh MC3500 tube amps. Unlike traditional left-right P.A. systems, this behemoth gave each instrument its own vertical array, and vocals emanated mostly from a center honeycomb cluster above the band.

Vocals, lead guitar, rhythm guitar, and piano each had its own channel and speaker array. Phil Lesh's bass guitar was piped through a quadraphonic encoder that sent a separate signal from each of the four strings to its own channel and set of speakers. Another channel amplified the bass drum, and two more channels carried the snares, tom-toms, and cymbals. Because each speaker carried just one instrument or vocalist, the sound was reportedly exceptionally clear and free of intermodulation distortion.

It projected high quality playback at six hundred feet with acceptable sound & projected for a quarter of a mile without degradation or delay speakers. Speakers sat behind the band so it was the monitors. It filled 4 semi trailers.

I find modern computerized eq and pa systems, for the most part, blow away the mostly muddy sound I remember from the late 70's and 80's (except for really good halls). I am too young to have heard the wall. Any A-goners remember the sound?
The Wall of Sound was an enormous public address system designed specifically for the Grateful Dead's live performances by legendary audio engineer and LSD chemist Owsley "Bear" Stanley.
IIRC, parasound's JCurl was one of its designers.
They used mostly 15" extended range F-131 speakers and compression tweeters in an horizontal array. These were JBL but sold as a Fender driver. The Wall I read was purchased by the Dave Mathews Band. It was not used for very long and broken up and now scattered remaining elements are unaccounted for. I read this and can't recall the citation.
They used mostly 15" extended range F-130 speakers and used horn compression tweeters in an horizontal array. These were all made by JBL but sold as a Fender drivers.
The Wall was purchased by the Dave Mathews Band when he started to play large venues. It was not used for very long and broken up. The scattered remaining elements are unaccounted for. I read this however I can't recall the citation.
The DMB purchased the Grateful Dead's final touring PA system in late 1995. This system was designed, sourced and built by Ultra Systems. This system was not the Wall 'o Sound.

The WoS was so large, complex, and costly to transport and maintain, it saw only a very limited life cycle. It would take an entire day (or more) to erect the scaffolding, arrays and de-bug the system prior to a show. At one point early on, Bear tried to convince the band that they really need two complete systems, in order to leap-frog over each other during tours. If you watch "The Grateful Dead Movie" shot during the Dead's October 1974 run,this was the swan song for the system, leading up to their hiatus from performing. Their self-imposed, slightly more than a year off, was the result of near financial ruin for the band, brought on by the Wall of Sound and an accounting scandal involving Mickey's father. When the band returned to performing live again, they did so without the Wall of Sound.

In addition to McIntosh amps, they also employed a number of Bob Carver's Phase Linear 400s. Jerry was partial to this amp in his guitar stack.
Thank you for this explanation Slipknot. It sounds much more realistic than the DMB buying the famous "wall". Is there any reference article on the composition of the Wall and anything in particular regarding the Fender speakers. If it is true that they used them I would be curious to know which Fender labled drivers they used.
I don't know of any band using a big or in this case ginormous sound system made from home audio components. Professional sound systems vary but are largely not used by audiophiles not because of the size or even expense but because of many accounts reporting they just don't sound very good.
The touring gear must be portable and durable. I am not at all aware of why these requirement may be a true obstacle in designing equipment that sounds good. The studio is a less harsh enviroment. Several pieces of equipment are highly desirable and legendary I think a JBL monitor which is named by a number 24### is such a piece. I have noted that other "near field monitors" in particular, seem to cross over to the home audio market.
I don't know why we are not using the incedibly inexpensive 1000W + amps I see advertised in the pro music e mails I never asked for and don't play music on anything other than stereos> Why not have 4 or 5000 watts to get some truly dynamic sound out of the new standard size 6.5 inch woofer . I don't know if they need a high voltage power line so maybe it just can't be done without a dedicated mains panel or having to the outlet used by the dryer It is one hell of a weird plug and huge. Setting up a system close or in the same area you wash clothes in may be hard and room treatments will be needed.
In my limited view the Pro Audio requirements are far different from Home Audio Reguirements. Most pro gear is designed far different from Home gear. Most Home gear is designed not to resonate. Most Pro gear is actually encouragedt to induce distortions. From pedals, Heads, cabinets etc.. Also most pro Audio is designed to be mounted in roll around racks. They also tend to be designed to withstand the rigors of being abused on the road and in many cases they can simply swap out output transistors without Elecrically realigning the entire amp. A regular Roadie can handle most repairs of Pro Audio gear. Their ability to handle the rigors of the road and ease of maintence seem to be opposed to how home gear is used.

my .02 cents
Here's a link to a diagram, description and photos courtesy of

The Wall of Sound
Mechans writes:
> Why not have 4 or 5000 watts to get some truly dynamic sound out of the new standard size 6.5 inch woofer .

You'll run into mechanical limits before you get to even 1000 Watts.

If you do want the head room, larger more sensitive speakers are a better way to get there since they won't suffer from thermal compression.
Hi, I heard this system many, many times. It really was special and had a unique sound unlike anything else I have heard. It sounded more like a huge stereo than a PA. I have worked my whole life in the pro audio world and that one system still stands out among people who work with live sound. An interesting thing was how they were able to use microphones in front of all of those speakers. Usually, you would not do that as you would get lots of feedback. Eac "mic" was actually two mic's that were right next to each other, just slightly offset, and wired in opposite polarity to each other. By wiring them 180 degrees out of phase, they cancelled each other out. This affected all sound other than a sound that was substantially higher in level in one mic. This required the band members to practically put their mouths on the mic when they sang. They sang only into one of the two mics. It was a great idea that really worked well! Of course the requirment to be on the mic was impractical for most bands. When Phil Lesh hit those low notes, this system was something to be remembered. During the following decades, now and then you would come across pieces of that old "wall of sound"
I just read back in this thread, and since I work in the pro audio market and also enjoy high end home gear I figured I would put in my thoughts. I have worked in the studio world as a designer and engineer, in live touring sound, as a consultant on large fixed installs and as a creator of audio products. I currently am the President of a consutling firm and a VP at a major pro audio manufacturer, where I define DSP based products. Each pro audio market has it's own unique requirments. In general, pros want the same end result as do home listeners, good sound. In the studio, we strive for accuracy. Live sound system operators look for light weight, lots of power, and the ability to stand up to constant abuse. In fixed sound systems, the focus is on reliability, sound quality, and intelligbility. Cinema focuses on sound quality per dollar.

The only place where pros desire distortion is in music creation, not reinforcement. Musicians use distorion and other effects. A guitar amp will intentionally introduce distortion, but not a PA amp. I have noticed that people seem to like distortion in China, but that is just an observation of mine.

So, why not use pro equipment in home settings? The answer is that you can, but you want to choose the correct equipment. Most pro equipment uses the same AC plug as home equipment. I have a few different systems at home. I have one that is based upon B&W Nautilus 801's, Ayre K1 and V1, along with their CD and a Logitech transporter. Another system uses Ayre and Thiel My surround system, which someday if I ever have the time will be a home theater integrates both home and pro audio equipment. I have five "old" B&W 801's, a QSC dual 18" very large cinema sub (it is used in lots of cinemas througout the world), three Crown Macro Reference (also known as Studio Reference I) power amps, and a QSC cinema power amp on the sub. It uses an Anthem D2 as the processor. So, I have home, cinema, and studio equipment in one system and it all works very well together. It has a different character from my my more "refined" systems, but they are all fun to listen to.

I have done side by side comparisons between my Ayre power amp and a QSC pro amp that is targeted to the touring and fixed install markets and has a huge amount of power. I used various high end speakers in doing so. My conclusion is that both amps sounded great. For home listening I had a slight preference for the Ayre, but the differences were not that huge. The QSC is a fraction of the cost of the Ayre. One thing to be very careful of is fan noise. In pro applications, other than studios, we just don't get too concerened about fan noise. Amps and other products are expected to operate normally at 50 degrees C day after day, year after year. A noisy fan in a home system can be annoying.

If anyone has any questions regarding the pro side, please reply. I think I am somewhat unusual in that I enjoy both sides of the audio industry.

If anyone has pics, please post!